Things You'll Need
- Black light
- Hydrogen peroxide
- Wood bleach
- 80-grit sandpaper
- Hand sander
- Wood stain
Instructions
Find the urine spots using a black light. These are available at many pet and hardware stores, and will let you find invisible urine in unfinished wood floors, carpet and upholstery.
Soak the urine stains in the unfinished wood with 3 percent hydrogen peroxide--this is the strength sold at drug stores. Saturate a rag with the hydrogen peroxide, place it over the stain, and cover that with plastic to keep it wet. Leave it for 24 hours. This method works if the urine was dilute, or hasn't penetrated too deeply into the wood.
Use a wood floor cleaner containing bleach if the hydrogen peroxide was ineffective in removing the stain. Follow label directions; most bleaching wood cleaners are left on the wood for 20 to 30 minutes, then rinsed off.
Allow the treated area to dry completely. The bleach should lighten the stain, which will probably now be lighter than the surrounding wood.
Sand the area with 80-grit sandpaper. If there are multiple stains or it's a very large spot, use an electric hand sander. Sand with the grain of the wood, along the length of the planks.
Apply wood stain to blend in the light area with the surrounding wood. Err on the side of caution and use a lighter stain than you think you may need at first: if you stain it too dark, it won't match and you'll still be left with a dark spot in the wood.